Antioxidants disrupt treatment
Supplement megadoses may cause cancer recurrence, says expert
PETALING JAYA: The over-consumption of supplements especially antioxidants among cancer patients could interfere with treatment for the disease, says a clinical pharmacist with the National Cancer Institute.
Azmi Nor Mohd Farez Ahmat said that “megadoses” of these supplements could also cause recurrence of these cancers.
He said the issue is a sensitive one among cancer patients and survivors, with studies showing that up to 60% of cancer patients consume such supplements.
“Most of these supplements if taken in doses recommended by oncologists should not have any side effects.
“But if taken in megadoses, especially antioxidants, this could have an effect on the effectiveness of the treatment,” he said during a webinar in conjunction with World Cancer Day 2021 yesterday.
He said radiotherapy and chemotherapy induce reactive oxygen species (ROS), which in turn destroys the formation of cancer cells.
A megadose of antioxidants could interfere with the effectiveness of the ROS, he said.
Azmi Nor, however, said there is no issue with taking foods that naturally contain antioxidants such as fruits, green tea, green vegetables, apricots and dark chocolate.
In a speech earlier, Health director-general Tan Sri Dr Noor Hisham Abdullah said that cancer was the main cause of death in private hospitals in 2018, contributing about 33%.
It is the fourth highest cause of deaths in public hospitals at 11.8% in that same year.
He said the most common forms of cancers among men were colorectal (16.9%), lung (14.9%), prostate (8.1%), lymphoma (6.6%) and nasopharynx (6.5%).
Among women, the most common cancers were breast (33.9%), colorectal (10.7%), cervical (6.2%), ovary (5.6%) and lung (5.5%). Dr Noor Hisham also said that 63.7% of cancer cases in the country were only detected during the late stages (three and four), and that this led to more complex treatments with higher costs.